• Journal of Magnetics
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• v.2 no.4
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• pp.147-156
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• 1997

An artificially modulated magnetic Co/Pd multilayer is one of the promising candidates for high density magneto-optic (MO) recording media, due to a large Kerr rotation angle in the wavelength of a blue laser beam. However, since multilayer structure, as well as amorphous structure, is a non-equilibrium state in terms of free energy and a MO recording technology is a kind of thermal recording which is conducted around Curie temperature (Tc) of the recording media, when the Co/Pd mulilayer is used for the MO recording media, changes in the magnetic properties are occurred as the amorphous structure do. Therefore, the assessment of the magnetic properties in the Co/Pd multilayer during interdiffusion is crucially important both for basic research and applications. As the parameter of the magnetic properties in this research, saturation magnetization and perpendicular magnetic anisotropy energy of the Co/Pd multilayer are measured in terms of Ar sputtering pressure and heat treatment temperature. Form the results of the research, we find out that the magnetic exchange energy between Co and Pd sublayers strongly affects the changes in the magnetic properties of the Co/Pd multilayers during the interdiffusion in ferromagnetic state. This discovery will provide the understanding of the magnetic exchange energy in the Co/Pd multilayer structure and suggest the operating temperature range for MO recording in the Co/Pd multilayer for the basic research and applications, respectively.

• Geomechanics and Engineering
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• v.33 no.6
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• pp.625-633
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• 2023

The volume changes associated with moisture or suction variation in expansive soils are of geotechnical and geoenvironmental design concern. These changes can impact the performance of infrastructure projects and lightweight structures. Assessment of unsaturated function for these materials leads to better interpretation and understanding, as well as providing accurate and economic design. In this study, expansive soils from different regions of Saudi Arabia were studied for their basic properties including gradation, plasticity and shrinkage, swelling, and consolidation characteristics. The unsaturated soil functions of saturated water content, air-entry values, and residual states were determined by conducting the tests for the entire soil water characteristic curves (SWCC) using different techniques. An attempt has been made to provide a prediction model for unsaturated properties based on the basic properties of these soils. Once the profile of SWCC has been predicted the time and cost for many tests can be saved. These predictions can be utilized in practice for the application of unsaturated soil mechanics on geotechnical and geoenvironmental projects.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.270.1-270.1
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• 2013

Zinc oxide (ZnO) is one of the most powerful materials for purifying organic pollutants using photocatalytic activity. In this study, we have introduced a novel method to design highly photoreactive flexible 3 dimensional (3D) ZnO nanocomposite [F-ZnO-m (m: reaction time, min)] by electrospinning and simple-step ZnO growth processing (one-step ZnO seed coating/growth processing). Significantly, the F-ZnO-m could be a new platform (or candidate) as a photocatalytic technology for both morphology control and largearea production. The highest photocatalytic degradation rate ([k]) was observed for F-ZnO-m at 2.552 h-1, which was 8.1 times higher than that of ZnO nanoparticles (NPs; [k] = 0.316 h-1). The enhanced photocatalytic activity of F-ZnO-m may be attributed to factors such as large surface area. The F-ZnO-m is highly recyclable and retained 98.6% of the initial decolorization rate after fifteen cycles. Interestingly, the F-ZnO-m samples show very strong antibacterial properties against both Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) after exposure to UV-light for 30 min. The antibacterial properties of F-ZnO-m samples are more effective than those of ZnO NPs. More than 96.6% of the E. coli is sterilized after ten cycles. These results indicate that F-ZnO-m samples might have utility in several promising applications such as highly efficient water/air treatment and inactivation of pathogenic microorganisms.

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1929-1930
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• 2005

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.957-958
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• 2004

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.160-160
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• 1999

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.194-197
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• 2003

The actively addressable carbon nanotube (CNT) emitters have been studied for stable and low-voltage driving field emission display (FED). The a-Si TFT and screen-printed CNT emitters were successfully integrated to fabricate the diode type active-matrix cathode and FED panel. Also, we propose a new FED architecture based on the actively controlled triode CNT emitters showing the properties of ideal triode type cathode with electron beam focusing effect.

• Honam Mathematical Journal
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• v.26 no.4
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• pp.559-587
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• 2004

We study some properties of intuitionistic fuzzy normal subgroups of a group. In particular, we obtain two characterizations of intuitionistic fuzzy normal subgroups. Moreover, we introduce the concept of an intuitionistic fuzzy coset and obtain several results which are analogous of some basic theorems of group theory.

• Journal of applied mathematics & informatics
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• v.7 no.3
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• pp.1029-1038
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• 2000

In this paper, we show that if x is a positively Lyapunov stable point of an expansive homeomorphism with the pseudo-orbit-tracing-property, then x is a periodic point or its positive limit set consists of only one periodic orbit, and their periods are predictable. We give a necessary and sufficient condition that a basic set is to be a sink or source. Also, we consider some dynamical properties of basic sets.

• International Journal of Knowledge Content Development & Technology
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• v.4 no.1
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• pp.39-51
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• 2014

The paper proposes that the Basic Concepts Classification (BCC) could serve as the controlled vocabulary for the Semantic Web. The BCC uses a synthetic approach among classes of things, relators, and properties. These are precisely the sort of concepts required by RDF triples. The BCC also addresses some of the syntactic needs of the Semantic Web. Others could be added to the BCC in a bottom-up process that carefully evaluates the costs, benefits, and best format for each rule considered.